<?php
class LtDbSqlAdapterPgsql implements LtDbSqlAdapter
{
    public function setCharset($charset)
    {
        return "SET client_encoding TO '$charset'";
    }
    public function setSchema($schema)
    {
        return "SET search_path TO $schema";
    }

    public function beginTransaction()
    {
        return "";
    }
    public function commit()
    {
        return "";
    }
    public function rollBack()
    {
        return "";
    }

    public function showSchemas($database)
    {

    }
    public function showTables($schema)
    {
        return "SELECT case when n.nspname='public' then c.relname else n.nspname||'.'||c.relname end as relname 
                FROM pg_class c join pg_namespace n on (c.relnamespace=n.oid)
                WHERE c.relkind = 'r'
                    AND n.nspname NOT IN ('information_schema','pg_catalog')
                    AND n.nspname NOT LIKE 'pg_temp%'
                    AND n.nspname NOT LIKE 'pg_toast%'
                ORDER BY relname";
    }
    public function showFields($table)
    {
        return "SELECT a.attnum, a.attname AS field, t.typname AS type, 
                format_type(a.atttypid, a.atttypmod) AS complete_type, 
                a.attnotnull AS isnotnull, 
                ( SELECT 't' FROM pg_index 
                WHERE c.oid = pg_index.indrelid 
                AND pg_index.indkey[0] = a.attnum 
                AND pg_index.indisprimary = 't') AS pri, 
                (SELECT pg_attrdef.adsrc FROM pg_attrdef 
                WHERE c.oid = pg_attrdef.adrelid 
                AND pg_attrdef.adnum=a.attnum) AS default 
                FROM pg_attribute a, pg_class c, pg_type t 
                WHERE c.relname = '$table' 
                AND a.attnum > 0 
                AND a.attrelid = c.oid 
                AND a.atttypid = t.oid 
                ORDER BY a.attnum";
    }

    public function limit($limit, $offset)
    {
        return " LIMIT $limit OFFSET $offset";
    }

    public function getSchemas($queryResult)
    {
        
    }
    public function getTables($queryResult)
    {
        
    }
    public function getFields($queryResult)
    {
        
    }
    public function detectQueryType($sql)
    {
        
    }
}